A species invasion mediated through habitat structure, intraguild predation, and parasitism

AbstractWhen two or more parasitoid species, particularly candidates for biocontrol, share the same target in the same temporal window, a complex of behaviors can occur among them. We studied the type of interactions (competition and intraguild predation) that existed between the nymphal parasitoids Anagyrus cachamai and A. lapachosus (Hymenoptera: Encyrtidae), two candidate neoclassical biocontrol agents against the Puerto Rican cactus pest mealybug, Hypogeococcus sp. (Hemiptera: Pseudococcidae). The surrogate native congener host in Argentina, the cactus mealybug Hypogeococcus sp., was studied to predict which species should be released; in the case that both should be released, in which order, and their potential impact on host suppression. In the laboratory we conducted experiments where different densities of the host mealybug were exposed to naive females of A. cachamai and A. lapachosus sequentially in both directions. Experiments were analyzed by combining a series of competitive behavioral and functional response models. A fully Bayesian approach was used to select the best explaining models and calculate their parameters. Intraguild predation existed between A. cachamai, the species that had the greatest ability to exploit the resource, and A. lapachosus, the strongest species in the interference competition. The role that intraguild predation played in suppression of Hypogeococcus sp. indicated that a multiple release strategy for the two biocontrol agents would produce better control than a single release; as for the release order, A. lapachosus should be released first.

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Advancing improvement in riverine water quality caused a non-native fish species invasion and native fish fauna recovery

Scientific Reports ◽

10.1038/s41598-021-93751-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Łukasz Głowacki ◽

Andrzej Kruk ◽

Tadeusz Penczak

Keyword(s):

Water Quality ◽

Fish Species ◽

Native Species ◽

Interference Competition ◽

Fish Fauna ◽

Species Traits ◽

Native Fish ◽

Biological Degradation ◽

Species Invasion ◽

Prussian Carp

AbstractThe knowledge of biotic and abiotic drivers that put non-native invasive fishes at a disadvantage to native ones is necessary for suppressing invasions, but the knowledge is scarce, particularly when abiotic changes are fast. In this study, we increased this knowledge by an analysis of the biomass of most harmful Prussian carp Carassius gibelio in a river reviving from biological degradation. The species' invasion followed by the invasion's reversal occurred over only two decades and were documented by frequent monitoring of fish biomass and water quality. An initial moderate improvement in water quality was an environmental filter that enabled Prussian carp’s invasion but prevented the expansion of other species. A later substantial improvement stimulated native species’ colonization of the river, and made one rheophil, ide Leuciscus idus, a significant Prussian carp’s replacer. The redundancy analysis (RDA) of the dependence of changes in the biomass of fish species on water quality factors indicated that Prussian carp and ide responded in a significantly opposite way to changes in water quality in the river over the study period. However, the dependence of Prussian carp biomass on ide biomass, as indicated by regression analysis and analysis of species traits, suggests that the ecomorphological similarity of both species might have produced interference competition that contributed to Prussian carp’s decline.

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The food web in a subterranean ecosystem is driven by intraguild predation

Scientific Reports ◽

10.1038/s41598-021-84521-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Andrea Parimuchová ◽

Lenka Petráková Dušátková ◽

Ľubomír Kováč ◽

Táňa Macháčková ◽

Ondřej Slabý ◽

...

Keyword(s):

Food Web ◽

Trophic Interactions ◽

Intraguild Predation ◽

Linear Models ◽

Niche Overlap ◽

Trophic Niche ◽

High Availability ◽

Large Prey ◽

Arthropod Predators ◽

Body Sizes

AbstractTrophic interactions of cave arthropods have been understudied. We used molecular methods (NGS) to decipher the food web in the subterranean ecosystem of the Ardovská Cave (Western Carpathians, Slovakia). We collected five arthropod predators of the species Parasitus loricatus (gamasid mites), Eukoenenia spelaea (palpigrades), Quedius mesomelinus (beetles), and Porrhomma profundum and Centromerus cavernarum (both spiders) and prey belonging to several orders. Various arthropod orders were exploited as prey, and trophic interactions differed among the predators. Linear models were used to compare absolute and relative prey body sizes among the predators. Quedius exploited relatively small prey, while Eukoenenia and Parasitus fed on relatively large prey. Exploitation of eggs or cadavers is discussed. In contrast to previous studies, Eukoenenia was found to be carnivorous. A high proportion of intraguild predation was found in all predators. Intraspecific consumption (most likely cannibalism) was detected only in mites and beetles. Using Pianka’s index, the highest trophic niche overlaps were found between Porrhomma and Parasitus and between Centromerus and Eukoenenia, while the lowest niche overlap was found between Parasitus and Quedius. Contrary to what we expected, the high availability of Diptera and Isopoda as a potential prey in the studied system was not corroborated. Our work demonstrates that intraguild diet plays an important role in predators occupying subterranean ecosystems.

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Assessing woodpeckers as indicators of bird diversity and habitat structure in managed forests

Biodiversity and Conservation ◽

10.1007/s10531-021-02164-0 ◽

2021 ◽

Author(s):

Tarun Menon ◽

Ghazala Shahabuddin

Keyword(s):

Habitat Structure ◽

Bird Diversity ◽

Managed Forests

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Intraguild predation dampens trophic cascades in shallow aquatic mesocosms in the subtropics: Implications for lake restoration by biomanipulation

Freshwater Biology ◽

10.1111/fwb.13739 ◽

2021 ◽

Author(s):

Hu He ◽

Xiaoyu Ning ◽

Kunquan Chen ◽

Qisheng Li ◽

Kuanyi Li ◽

...

Keyword(s):

Intraguild Predation ◽

Lake Restoration ◽

Trophic Cascades ◽

Aquatic Mesocosms

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Simulations with Australian dragon lizards suggest movement-based signal effectiveness is dependent on display structure and environmental conditions

Scientific Reports ◽

10.1038/s41598-021-85793-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Xue Bian ◽

Angela Pinilla ◽

Tom Chandler ◽

Richard Peters

Keyword(s):

Research Methods ◽

Environmental Conditions ◽

Comparative Studies ◽

Habitat Structure ◽

Signal Transmission ◽

Lizard Species ◽

Local Adaptations ◽

Signal Divergence ◽

Colour Signals ◽

Optimal Signal

AbstractHabitat-specific characteristics can affect signal transmission such that different habitats dictate the optimal signal. One way to examine how the environment influences signals is by comparing changes in signal effectiveness in different habitats. Examinations of signal effectiveness between different habitats has helped to explain signal divergence/convergence between populations and species using acoustic and colour signals. Although previous research has provided evidence for local adaptations and signal divergence in many species of lizards, comparative studies in movement-based signals are rare due to technical difficulties in quantifying movements in nature and ethical restrictions in translocating animals between habitats. We demonstrate herein that these issues can be addressed using 3D animations, and compared the relative performance of the displays of four Australian lizard species in the habitats of each species under varying environmental conditions. Our simulations show that habitats differentially affect signal performance, and an interaction between display and habitat structure. Interestingly, our results are consistent with the hypothesis that the signal adapted to the noisier environment does not show an advantage in signal effectiveness, but the noisy habitat was detrimental to the performance of all displays. Our study is one of the first studies for movement-based signals that directly compares signal performance in multiple habitats, and our approach has laid the foundation for future investigations in motion ecology that have been intractable to conventional research methods.

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